Hi chaps, the carpet in my driver's footwell is often damp, especially in the winter. I can't find any rain leaks, and the targa drains aren't blocked. I'm not losing any coolant either (at least noticeably) - it does seem to taste a bit like coolant but I might be already intoxicated...

 

The whole area behind the pedals just seems to get covered in condensation, so much so that there's surface rust (hard to see but the shiny parts at the top of the picture are wet):

 

 

Any ideas on the cause? Could it be rain dripping in via the throttle cable or master cylinder? Or is it just because of the weather being damp? Heater matrix?

 

Thanks!

Check the little gate valve on the pipes going to heater matrix, the seal on the shaft can leak on these

Having said that, your pic is taking looking up vertical right? Is the actual floor carpet getting wet?

Initial jump would be heater matrix?

Yep, it's looking up and there's moisture pretty much all over, but the carpet is also wet (not enough to squeeze out water, but damp).

 

I was wondering heater matrix, but the heater works fine and the coolant level doesn't move (over 1+ year).

 

Thanks for the tip on the gate valve, I'll take a look!

Heater will still work with a small leak, get a pressure tested on the cooling system and check for small leaks around your matrix and pipe work leading to it, ideally you want to know for sure if this is coolant your finding on floor or rainwater/moisture to help find the cause.

I had a leak in an old zed, I fitted brand new door and targa seals etc and could cure it. Eventually with carpet removed I could see it was coming in at the overlap join half way up the bulkhead behind and above the pedals.

The car had been bumped at some point and the join had been disturbed in the impact causing an ingress of water at times.

Good luck with it.